Refrigerator with humidity control



Patented July 14,` 1942 UNITED? STATI-:s

PATENT OFFICE n 2,289,728 l aaraleanaroa Wrrn nUMmrrY ooNrnoL ClydeMalin Rees, White Plains, N. Y., assignor to George A. Rees, WhitePlains, N. Y.

tApplication April 25, 1939, Serial No. 269,831

6 Claims.

air in food storage compartments in a positive and efficient manner,simulating the advantages of the ice-boxes already known to the art.

More specifically, the object is to provide refrigerating compartmentsof refrigerators having systems for circulating refrigerant -with meansfor positively introducing and controlling `the water. vaporof'therefrigerating air-in such compartments, as well as the temperaturethereof, so that meats, vegetables, and similar articles will not bedehydrated while being kept therein. Another object of the invention isto provide a simple and positive means in association with the coolingelements of refrigerators for the controllable introduction of watervapor directly into the refrigerating air.)

Another object is to provide humidifying means for'refrigerators whichis adapted to maintain a relatively large amount of grains of moisturein the air which is circulated in a refrigerating compartment,irrespective ofbatmospheric conditions. y Still another object istoprovide a refrigerator having'a plurality of refrigeratlngcompartments I Ycooled by' a common system with'temperature temperingmeans associated with the cooling elel.ment in a selected compartment insuch a way as to modify the temperature gradient of the circulated airto get a desired cooling effect without changing the system, forexample, reducingy the vgradient so asto avoid undue moistureprecipitation on the cooling element.

Other objects of the invention will in part be obvious and will in partappear hereinafter,`

The invention accordingly comprisesthe fea-l ,tures of construction',combination of elements and arrangement of parts, which willbeexemplified in the construction hereinafter set forth-and the scope ofthe invention will -be indicated in the claims.

For a fuller understanding of the nature and objects of the invention,reference should be had to the following detailed description taken inconnection with the accompanying drawings, in

- which:v

Fig. l shows a front elevation of a typical domestic refrigerator of atype to which the present invention'is applicable;

Fig. 2 is a vertical section, taken on the line 2,2 of Fig. 1,' showinga refrigerating compart-u ment with means for cooling and humidifyingthe same in accordance with the invention;

Fig. 3 is a schematic diagram showing' means 60 (on cs2-3)' formaintaining automatically desiredtemperatures in the-compartments of therefrigerator shown in Fig.- 2; l Fig. 4 is afragmentary sectional view,similar to Fig. 2, illustrating a modified form of the invention:

l Fig.'5 is a fragmentary sectional view, taken on the line 5-5 of Fig.4, illustrating certain constructional details thereof;

Fig. 6 is a fragmentary vertical sectional view,

illustrating still another modified-form of the invention: andl Fig, 7isa fragmentary view showing -details of a control element lthat may beemployed in the practice of the invention.

Referring now to the drawings, and particularly to Figs. 1 and 2,- arefrigerator of the domestic type is shown generally at I0. providedwith upper and lower compartments denoted re spectlvely Il and `i2, to'which access is'had. by

doors opening at the front in the usual mannen The compartments Il andIZ are 'here shown as of the cold wall type, i. e., they aredouble-walled vessels in the enclosed space of which a refrigerant iscontained or circulated. The refrigerant contained in the enclosedspaces may be a secondary refrigerant or brine that is cooled by aprimary refrigerant admitted to the respective en-` closed spaces of thecompartments by an expan- 34') sion valve, as shown at I3 and at Ilfonthe compartments il and vi2' respectively. Such primary refrigerantis arranged to circulate in coils I3' and Il' disposed in the enclosedspaces of the respective compartments and connected` to 35 therespective expansion valves. These coils. have outletconnections shownrespectively at i5 and. I6. The primary refrigerant for compartments iland l2 may be any suitable refrigerant, for ex'- 0 ample, ethylchloride, which is supplied from a common system having a compressorshown` generally at 20, disposed in an unin'sulated compartment inthebase' of the refrigerator l0. [Such compressor is arranged to dischargecompressed refrigerant into condenser coils indicated sym- `bolically at2l, from the base of which the cooled refrigerant is led by a conduit 22tothe enclosed spaces, in which are located the cooling coils conductingthe primary refrigerant. It is 5'0 to be understood that these coolingcoils are immersed in the secondary refrigerant and aretapped into theconduit leadingrespectively'from the expansion valves I3 and il. Theadvantage of using botli'primary and secondary refrigerants is readilyseen in that it permits the use of a low boiling point refrigerantwithout lowering the surface temperature of the walln of the enclosedspaces to the `point where the circulating air will be dehumidiied. Areturn conduit 23 is similarly connected to the outlets I5 and it of thecoolingcoils and led to an inlet of the compressor 20. The systempreferably has a power-driven ventilating fan, shown at 24, for coolingthe coils 2|, the power being advantageously had from that which drivesthe `compressor,here shown as an electric motor 25.

The compartment may be describedl as a freezing compartment, inasmuch asit is adapted to have means disposed therein for supporting ice-cube-trays and the like. The compartment I2, however, is intended for thepreservation of articles of food, and may be described as therefrlgerating compartment. The temperatures desired in thesecompartments' are preferably different-and are hence independentlycontrolled. An arrangement for achieving th'is is shown in Fig. 3 whereAI1 and i3 denote the sensitive elements of the thermostatic means whichare disposed respectively in thecompartments and I2. These sensitiveelements may be of any suitable type, for example, of the expanding uidtype, in which a heat sensitive fluid operates an expansible element fordoing the Workof oper- I ating the primaryrefrlgerant controlling valvesand the like, such mechanism being diagrammatically indicated in Fig. 3by the blocks I9 and I9'. e

The control elements I9 and I9 are shown arranged for moving the -valvesI3 and I4 independently through valve rods |3| andMI. By

such means, refrigerant may be admitted selectively whenever thetemperatures of the respective compartments rise above predeterminedvalues. These control elements are. also preferably arranged 'to set thecompressor 20 into operwith an overflow connection V39 in order that apredeterminedl water level may not be exceeded at any time in the pan35.

The body of water introduced through the nozzle 36 into the panl 35 isinvariably at a higher temperature than that desired to be main# tainedin the refrigerating compartment I2. In consequence, the amount of wateradmitted is' adjusted so that the water in the pan has a desiredtemperature tempering effect which substantially raises the temperatureof theair being circulated by gravity Nabove its dew point and preventsits otherwise being too rapidly cooled. This higher temperature is alsoseen to be of advantage in accelerating the evaporation of water fromthe surface of the pan to a point approach` ing Isaturation during theperiod when the walls of the compartment are being cooled.

The evaporation of water into the air circulate V ing in the compartmentI2 may be further accelerated by introducing a porous body containing anumber of capillary passages, for example, a body of moist clay,hardwood charcoal, or activated carbon. Such block of porous material isindicated at 39 and provides a relatively large l upper or exposedsurface that is always moist, and

, quickly humidifles the air circulating in the com` s compartments Iproperly setting the automatic devices |9 and I9',

ation whenever an expansion valve is opened.'

Accordingly, the elements I9 and |9 are arranged to actuate suitablemotor control means. To this end, they are connected in parallel to eachother but in series with thev source of current. This latter issymbolically shown as a pair of alternating current bus bars 26. Thewiring arrangement connecting this source to motor 25 comprisesamainconductor leading -from onerside of the buses 26 and provided withparallel taps 3| and 32 leading to each of the control elements |9 andI9'. From the other side ofy the elements |9 and I9 conductors 29 and29' lead in parallel to the conductor 28 which'is connected to a motorterminal. The circuit is completed by another con- V ductor 21 leadingfrom the other motor terminal to the other'side of the bus bars. Thefood compartment I2 of the refrigerator here shown is thus providedthrough its cold walls with cooling means that lowers the temperature ofthe air circulated in the compartment to a desired low value, which ispreferably above the dew point for the atmospheric conditions to whichthe refrigerator is subjected. l

Positive means for humidifying the compartment are, in accordance withthe invention, associated with the refrigerating compartment I2,Y

the means in this instance comprising a pan= 35, located in thecompartment at .a point relatively remote from its side walls in aregion of relatively high temperature, into which pan water isdischarged from a nozzle 36 that is cooperatively disposed above the panand connected through the wall of the refrigerator to a water main 31;the latter being advantageously connected with the city water-supply.The water supplied to pan 35 by nozzle 36 is provided with a positivecontrol in the form of a-valve 38 introduced in the connection leadingfrom the pipe 31 to the nozzle 36. The pan 35 is also provided partmentI2.

'Ihe operation of the refrigerator is believed to be sulcientlyindicated in th above, it being Aapparent that the temperatures desiredin the and I2, are maintained by exemplary details of which are shown inFig. 7.

Referring to Fig. '7, a valve stem I3| is seen'to be extended into anenclosed compartment |3a which may be a small iron receptacle withremovable cover, the receptacle being arranged to house an expansible'bellows |30 to which is connected a fluid conduit |13: that communicateswith the sensitive element I1. By such arrangement, the lower wall ofthe bellows |30 is free to move up and down, and has an actuating column|32 connected thereto, on which an adjustable follower |33'is securedfor engaging with one arm of a lever |34 that actuates the Valve rod|3I, the lever and the column |32 being resiliently held in operativeengagement by means of a spring- |35. The column |32 is also providedwith an adjustably positioned arm |36 for engaging with one end of apivoted lever |39 which trips the contact making element |40 of anenclosed arc type of make-and-break ldevice, such as a mercury switch,that is connected at one end with conductor 3| through a pigtail |31,the other end being connected to conductor 29 through a pigtail |38.Thus, by suitably adjusting the follower |33 and the arm |36 on thecolumn 32, a control maintaining substantially any desired operatingcondition o of its associated expansion valve and the motor 25 may behad.

I' compressor"`2|l""'is .tapped by a connection I3 which has anexpansion valve therein at M and Here, the refrigerator has leads to acooling coil 45 inan open tank r pan 46 that 'contains a suitable.temperature tempering liquid, such as brine, and is dis-.

- posed inthe upper part of compartmentj'42. The coil 45 has an outletconnection 41 thatileads to .y the return connection 23.

'y In order that the secondary refrigerant or e brine in pan 46 mayinotonly lower the temperhas an outlet connection 49 provided .with a plu-'-rality ofnozzles 56 distributed over the top of the pan 46.y'Ihearrangement of these nozzles `is preferablysuch as to spray the.brine upwardlyinto the air in the compartment, any unevaporated sprayfalling back into the body of liquid in the pan 46. In order that thisbrine may becirculated to an extent which lowers the temperaturethe pan46 is provided with a sump 5I at its bottom from vwhich a pump inletconnection 52 leads to the inlet endof pump 48. Autovmatic control forthe circulation'of the brine is also preferably provided.v To this end,a temperature controlling means is employed, comprising a sensitiveelement 53, arranged toactuate acontrol element 54, which may .besimilar to that shownin Fig. 7 and arranged to actuate both aasavaa 5this motion, and is hence bothcool'edand humidifled by the4 secondaryrefrigerant or brine circulated and sprayed in compartment 42.' In thismanner, the tempered cold wall effect-is achieved `by the forcedcirculation of a secondary refrig-` erant. 1 -A third form of theinvention is shown in Fig.'

.6,1m which 6I denotes an upper freezing compartment of therefrigerator, while 62 denotes a lower refrigerating compartment. vinwhich cold walls are not directly employed, but a cold wall eilect isachievedby the use of both secondary and tertiary refrigerants. Here,the primary the expansion valve 44 and a makeand break forl the circuitssupplying'power to a motor 55 coupled to drive the pump 48.

The brine thus circulated is seen toV serve as a secondary refrigerant.at a Ahigher temperature than the primary refrigerant circulated `in thecoil 45 and is adaptedin its circulation to introduce a relatively largenumber of grains of moisture directly into the air circulated in thecornpartment 42.

In order to achieve direct impingement by the spray from nozzles 50 ofsubstantially all the air being circmted in compartment 42,. bamlng.

means are preferably employed, ofv a character adapted to direct theimpingement and assist in inducing circulation. An arrangement'ofbailles 'of this character is shown in` Fig. 5,'where a main baffle 56is disposed horizontally across the main -space in the upper portion ofthe compartment 42 but whose ends clear the side walls of thecompartment by a substantial distance.` Superior auxiliary bailles 51are disposed above the nozzles andto one side, such bailies clearing theside walls of the compartment by a less distance than the main bailles56. Inferior bailles 56 are also preferably disposed below the mainbaille 56 in substantially the same position asthe bailles 51. "Toassist in inducing circulation, a thin metallic plate 59, which maybedescribed as a vertical baille, is disposed adjacent each or the sidewalls but clearing thesame in all directions by small distances, theclearances being such that eachl plate `5!! fits snugly against theadjacent edges of baiiles 51 and 58. In this manner, the circulation ofair which may have been .warmed by absorbing heat from an article orarticles being refrigerated in compartment 42, rises in the spacebetween the vertical bailies 59 and the side walls of compartment 42,land moves horizontally over the baiiies 51 and thence downwardlythrough the spray from nozzles 50 and then about the sides of the brinepan 45 to descend centrally into the cooling compartment through thespace between the baffles 56. Substantially-the whole body of air in thecompartment 42 partakes of Vrefrigerant circulated achieves itslrefrigerating eilect in'accordance withl the so-called absorptionprinciple, the compartment 6| being shown provided with a coolingelement 63,. the front endl of which is adapted to house ice ltrays formaking ice-cubes, while the rear portion 63' is adapted for cooling thesecondary refrigerant. The cooled secondary refrigerant is led from thisportion of the cooling element through a conduit 64 to a cooling coil 65in a closed brine tank or vessel 66, the connection 64 advantageouslyhaving an automatically controlled expansion -valve 64a: disposedtherein, the secondary refrigerant when warmed by the brine in vessel66- -passing out through the connection 61 back to an upper portion loi!the coolingv element at 63'. Here, the cooling of the air -circulatingin the compartment 62 is accelerated by the provision of a plurality ofcooling fins 68 on the vessel 66,

these operating in conjunction with oneor more haines. as .shown at 69,which may be similar to those shown in Fig. 5. The circulation of thel`primary refrigerant for thecooling element68 is insured by theprovision of, an exteriorelement, shown symbolically at 10, the powersupply for which `may be throughgas for heating. In this form of theinvention, the air is humidiiled `by evaporating water from the surfaceof a water pan 1I, which is disposed in the upper part of thecompartmentv 62 on a shelf 12, the pan having a detachable overflowconnection 13 leading directly through the wall of the refrigerator fordischarge into a sewer or other sink. The f supply of water' for tho pan1| is had from a connection 14 leading from the city water-supply to adoor-actuated valve controlled device, shown generally at 15. To thisend, the valve devicer 15 comprises ava1ve casing-16 having aspring-lifted valve element 11, the stem of which is prolonged as avalve rod 16 having a button 18 on its outer end in engagement with theinner surface of a door 8,0 that .affords access to the compartment 62.

By this arrangement, the valve element 11 is normally seated when thedoor is closed, and

the air circulating in the compartment 62 passes downwardly over thebrine tank 66where, if it be dehumidiiled.I it is rehuinidiiied byevaporating water from the surface of the pan 1I. 'I'he air circulatingis thus substantially saturated by evaporation at the water'surface inpan 1l, as long as equilibrium conditions obtain with the door -86closed. When, however, the door is temperature gradient between the aircirculated 4 Y aaeaves ing being positively accomplished in each of thel forms of the invention here illustrated. There is thus substantiallyno tendency for the air cirs culating to dehydrate food or otherhydrated articles stored in the refrigerating compaent.

Since certain changes lmay be made in the i5 above construction anddiderent embodiments of the invention could be made without departf ingfrom the scope thereof, it is intended that all mattercontained in theabove description or shown in the accompanying drawings shall be 2ginterpreted as illustrative and not in a limiting sense. r v

Having described my invention, what I claim as new and desire to secureby Letters Patent is:

1. In a refrigerator the combination comprising, a food storagecompartment containing air, a system for circulating primary refrigerantin'- cluding a cooling element, a vessel in the upper part of saidcompartment containing a body of liquid adapted to be cooled by saidcooling ele- 3o ment and to cool the air which is freely circulatedsubstantially solely by gravity, humidity ycontrolling means forintroducing water Vapor directly into-gravity circulated air including arelatively low pressure nozzle associated with the body of liquid insaid vessel, said means being' located in said compartment at a pointremote from the side walls thereof in a region ofrelatively hightemperature, means forv circulating primary refrigerant in said systemto cool the 4o body of liquid whereby it serves as secondaryrefrigerant, and thermostatic means' lcontrolling the circulation ofsaid primary refrigerant so as to 4maintain a desired temperature of theliquid.

2. Ina refrigerator the combination, comprising, a food storagecompartment containing air,

. a ,system for circulating primary refrigerant including a coolingelement, humiditycontroliing -means for introducing water vapor directlyinto gravity circulated air including aA plurality of relatively lowpressure spraying nozzles, said means being located in said-compartmentat a point remote from the side walls thereof in a region of relativelyhigh temperature, a vessel holding asecondary refrigerant comprising abody of brine D each of saidcompartments connectedin parallel connectedto supply spray to said nozzles and to collect that which issuestherefrom, means forA forcing the circulationv of said brine, saidcooling element being arranged for cooling thefbrineyz'ith the latterbeing adapted for cooling theair'which -60 is freely circulatedsubstantially solely; bygr'avity, and thermostatic means for controlling'both the circulation and the temperatureof--the brine.

3. In a refrigerator the combination comprising, a food storagecompartment containing air,

a system 'for circulating; primary' refrigerant including a coolingelement, humidity controlling means for introducing water vapor;directly into gravity circulated air including a plurality of relativelylow pressure spraying nozzles, said holding a secondary refrigerantcomprising a body of brine associated with said humidity controllingmeans and adaptedfor cooling the' air which is freely circulatedsubstantially solely by gravity, said cooling element having atleast aportion immersed in the body of brine to permit the circulation ofprimary refrigerant therethrough, thermostatic means for maintaining thetemperature of the brine at a desired value, and

baille means for causing the gravity circulated air to be tempered bypassage about the body of brine.

4. In a refrigerator having a plurality of com# partments one of whichcontains air to be refrigerated, the combination with asystem com'- rnonto said compartments for circulating primary refrigerant and includingcooling elements one for each of said compartments, of means in saidlair-containing compartment at a point remote from the side walls thereofin a region of relatively high temperature for holding a body of liquidadapted for cooling the air which is freely circulated substantiallysolelyv by gravity with the cooling element 'for said compartment beingar-l ranged for cooling the body of liquid, a plurality of sprayingnozzles for humidifying air disposed in said compartment, meansconnected to said liquid holdingv means to supply spray to said nozzles,means for collecting and returning to said liquid holding means spraywhich is unevaporated `by gravity circulated air, and means fordirecting gravity circulated air into contact with said.-

spray.

5. In a refrigerator having a plurality of coin-l partments one of whichcontains air to be refrigerated, the combination with a system common tosaid compartments for circulating primary refrigerant and includingcooling elements one for l .each of said compartments, of means insaidaircontaining compartment at a point remote from the side wallsthereof in a region of relatively high temperature Afor holding a bodyof liquid adapted to be cooled by one of said cooling elements and tocool the air which isA freely circulated substantiallyHy solely bygravity, baiiies for directing gravity circulated air to pass over thebody of liquid, xmeans associated with the body ofV liquid forintroducing grains of moisture directly.`

into gravity circulated air and means for controlling the temperature ofthe body of liquid.

(i.4 In a refrigerator having a plurality of segregated compartments oneof which contains air to .be refrigerated, the combination with a systemcommon to said compartments for circulating refrigerant and includingcooling elementsone for of said air-containing compartment containingsecondary refrigerant adapted for cooling the air which is freelycirculated substantially solely by gravity with one of said coolingelements' im? mersed in the secondary refrigerant, humidity"4controlling means comprising a relatively low pressure spraying nozzlelocated above said vessel, means to circulate secondary refrigerant fromsaidV vessel to said nozzle, baiiles for directing gravity circulatedair over said vessel, and ther-l mostatic means for controlling both thecirculation of said secondary 'refrigerant and saidV primary refrigerantflow control means.

' CLYDE MALIN REES.

